Added cross building for different SBT versions.
Added support for native packaging drop-in resources
Merge pull request #7 from metasim/ant-classpath-tweak

Added support for native packaging drop-in resources
Merge branch 'master' of https://github.com/kavedaa/sbt-javafx.git
Added default value for pkg resources dir.
Replace string interpolation with simple concatenation so we can
cross-build for older SBT versions (which use older Scala versions).